1. Field of the Invention
The present invention relates to a surface modified nanoparticle and preparation method thereof, more particularly to a nanoparticle surface modified with a phenol compound having dienoic bonds and preparation method thereof.
2. Description of the Prior Art
With advance of nanotechnology development, there have been numerous and versatile nanotechnology products in our daily life. Nanomaterials surface modified with specific molecules have been broadly applied in many aspects. For example, nanoparticles made of magnetic iron oxide, gold, CdSe quantum dot may be used as vehicles and surface modified with special functional molecules, e.g. organic compounds, fatty acids, DNA, so as to be applied in drug delivery, environmental analysis and other particular purposes.
When processed to nanometer-size, conventional materials may be varied in their physical, chemical properties and biocompatibility. Particles or structure material sized between 1 and 100 nanometers, i.e. nanoparticles, may be uptaken into living organisms via breath, diet, blood vessel injection, skin contact and so on. For example, nanoparticles suspended in air may be inhaled into lungs of living organisms or nanoparticles existing in contaminated water or food may enter into gastrointestinal tracts. In addition, nanometer-sized medicine may enter living organisms via intravenous injection, or applying external medicine or cosmetics containing nanoparticles on skin.
Nanoparticles, especially non-organic nanomaterial, are characterized in quick absorption, slow excrement and therefore long retention period. The nanoparticles that retain in the living organism might result in tissue inflammation, necrosis and fibrosis in some cases, and might cause mitochondria deformation and cell death in the other cases.
The toxicity of nanoparticles may depend on their own material properties, including biocompatibility, physical property, chemical property, mechanical property, radius, shape and so on. In addition, the solubility and concentration of nanoparticles that enter tissues and cells also contribute to the toxicity.
It is currently thought that the primary mechanisms for nanoparticle toxicity are cell-generated peroxide radicals. Reactive oxygen species (ROS), including O2−, H2O2, —OH and so on, are characterized in free radicals having unpaired electrons and therefore are highly active and might attack important molecules, e.g. proteins, nucleic acids and fatty acid, resulted in cellular oxidative damage and further aging or disease.
It would be very difficult to keep alert since one can not be aware of being exposed in environment containing nanoparticles. Although nanoparticles have been broadly applied, we still haven't understood the mechanisms for absorption, distribution, metabolism, excretion and toxicity after nanoparticles are uptaken into human. Therefore, it is now an urgent and important mission to provide safe nanoparticles for human.